Upload
others
View
23
Download
0
Embed Size (px)
Citation preview
Transoral endoscopic thyroidectomy vestibular approach(TOETVA): indications, techniques and results
Angkoon Anuwong1 • Thanyawat Sasanakietkul1 • Pornpeera Jitpratoom1•
Khwannara Ketwong1 • Hoon Yub Kim2• Gianlorenzo Dionigi3 • Jeremy D. Richmon4
Received: 8 September 2016 / Accepted: 3 July 2017! Springer Science+Business Media, LLC 2017
AbstractIntroduction The Transoral Neck Surgery (TONS) Study
Group was established at the 1st International Thyroid
NOTES Conference in February 2016 with the intention ofstandardizing and refining thyroid NOTES techniques,
including both transoral endoscopic and robotic thy-
roidectomy approaches. Herein, the authors report themodification of indications, preparation, and step-by-step
explanations for operative techniques, as well as results and
postoperative care for transoral endoscopic thyroidectomyvestibular approach (TOETVA).
Methods Between February 2015 and December 2015, a
total of 200 patients comprising 8 males (4%) and 192females (96%) underwent TOETVA using 3 laparoscopic
ports inserted at the oral vestibule. Of these patients, 111
presented with single thyroid nodules (55.5%), while 66patients had multinodular goiters (33%), 12 had Graves’
disease (6%) and 11 had papillary microcarcinoma (5.5%).
The CO2 insufflation pressure was maintained at 6 mmHg.Each surgery was performed using laparoscopic instru-
ments and ultrasonic devices.
Results TOETVA was performed on 200 consecutivepatients. No conversion to conventional open surgery was
necessary. Average tumor size was 4.1 ± 1.78 cm
(1–10 cm). Median operative time was 97 ± 40.5 min(45–300 min). Median blood loss was 30 ± 46.25 mL
(6–300 mL). Mean visual analog scale measurements were
2.41 ± 2.04 (2–7), 1.17 ± 1.4 (0–5), and 0.47 ± 0.83(0–3) on the first, second, and third days, respectively.
Temporary hoarseness and hypoparathyroidism occurred in
8 patients (4%) and 35 patients (17.5%), respectively. Nopermanent hoarseness or hypoparathyroidism occurred.
Mental nerve injury occurred in 3 patients (1.5%). One
patient (0.5%) developed a post-operative hematoma thatrequired open surgery. No infection was identified.
Conclusion TOETVA was shown to be safe and feasible
with a reasonable surgical duration and minimal painscores. This approach shows promise for those patients
who are motivated to avoid a neck scar.
Keywords Transoral endoscopic thyroidectomy !Thyroidectomy ! TOETVA ! Transoral ! Endoscopicthyroidectomy ! Transoral neck surgery
Open thyroidectomy is currently the standard surgery
option for thyroid diseases. However, this approach leaves
an unavoidably visible neck scar. Many modified tech-niques have been developed to reduce the size of the neck
scar, including minimally-invasive open thyroid surgery
[1, 2] and video-assisted thyroidectomy (MIVAT) [3].Many of the alternative approaches for pure endoscopic
thyroidectomy move the wounds to other parts of the body
& Angkoon [email protected]
1 Minimally-Invasive and Endocrine Surgery Division,Department of Surgery, Police General Hospital, 492/1 RamaI Road, Pathumwan, Bangkok 10330, Thailand
2 Department of Surgery, KUMC Thyroid Center, KoreaUniversity Hospital, Korea University College of Medicine,Seoul, South Korea
3 Division of Endocrine Surgery, Department of HumanPathology in Adulthood and Childhood ‘‘G. Barresi’’,Department of Surgical Oncology, University Hospital -Policlinico ‘‘G.Martino’’, University of Messina,Via Consolare Valeria 98125, Messina, Italy
4 Department of Otolaryngology Head Neck Surgery,Massachusetts Eye and Ear Infirmary, Harvard MedicalSchool, Boston, USA
123
Surg Endosc
DOI 10.1007/s00464-017-5705-8
and Other Interventional Techniques
such as the axilla, breast, or post-auricular area [4–7].
However, cutaneous scars are still apparent. Further, theseapproaches require a large amount of flap dissection, which
contradicts the notion that they are truly minimally-
invasive.Recently, Natural Orifice Transluminal Endoscopic
Surgery (NOTES) for thyroidectomy was developed [8, 9].
This surgical technique completely avoids visible cuta-neous scarring with an approach through the oral cavity.
Two techniques have been described, including 1) a sub-
lingual approach, which causes severe tissue damage with ahigh complication rate [10–12], and 2) an oral vestibular
approach [13, 14]. The authors recently reported another
refined transoral endoscopic thyroidectomy vestibularapproach (TOETVA) in the first 60 human cases, which
showed encouraging results with minimal complications
[15].After the 1st International Thyroid NOTES Conference
was held in Bangkok, Thailand in February 2016, an
international Transoral Neck Surgery (TONS) Study Groupwas established to further standardize and refine the thyroid
NOTES technique, which includes both endoscopic and
robotic instrumentation. To this end, the largest single-in-stitutional cohort of TOETVA was assembled. The data
have been reviewed in this report by members of a task
force who have experience performing transoral thy-roidectomy in their respective institutions. The first TONS
Study Group report to describe modification of the indi-cations, preparation, techniques, as well as postoperative
care for TOETVA has been provided herein.
Methods
Perioperative preparation
All surgeries were performed by 3 surgeons at PoliceGeneral Hospital in Bangkok, Thailand, a tertiary referral
hospital. Patients were informed of their potential surgical
options, which included conventional open surgery,TOETVA and other techniques of remote-access endo-
scopic thyroidectomy performed at the institution. Discus-
sion of the various advantages and disadvantages of eachapproach, with consideration of the nature of the disease as
well as their individual health issues was included in the
informed consent process. Ultimately, patients elected theTOETVA approach if they were deemed appropriate sur-
gical candidates. The study received approval by the ethics
committee of Police General Hospital.Inclusion criteria includes a thyroid gland of a diameter
not exceeding 10 cm comprising (1) a benign thyroid
nodule(s), (2) papillary microcarcinoma with no evidenceof metastasis, (3) follicular neoplasm, or (4) well-
controlled Graves’ disease, as previously described [15]. In
addition, we included grade 1 substernal goiters in thepresent study (above aortic arch). Early experience
demonstrated that TOETVA can be done safely in patients
who had previously undergone surgery or radiation at thechin and neck area. Moreover, patients with dental braces
were no longer contraindicated (Table 1).
All patients had routine investigation including thyroidfunction tests, neck ultrasonography, and fine needle
aspiration. Patient preparation was identical to that forstandard open surgery. Dental evaluation by a dentist was
only necessary for patients with severe oral hygiene issues.
No routine dental examination was required.
Surgical technique
The patient was placed in a supine position. The shoulders
were raised with sandbags and the neck was extended
slightly. All patients were administered general anesthesiawith nasotracheal intubation. The neck and lower face were
prepped and draped from the lower end at the level of the
sternal notch, the upper end at the level of the upper lip,and the lateral aspects of the neck. Pre-operative admin-
istration of 1.2 g of intravenous Amoxicillin with Clavu-
lanic acid was injected 30 min before skin incision. Theoral cavity was cleansed using 0.05% Hibitane in water.
The surgeon stood at a point over and above the head of the
patient, while the assistant and camera operator stood oneither side of the patient’s neck (Fig. 1).
Incisions and port insertion
The procedure was initiated with a 10 mm scalpel incision
in the center of the oral vestibule just above the inferiorlabial frenulum (Fig. 2). This incision was made in a more
anterior location compared to the previous technique [15].
Monopolar electrocautery was used to dissect in the centralincision through the mentalis muscle down to the tip of the
chin. Next, 30 mL of 1:500,000 adrenaline–saline solution
(1 mg adrenaline in 500 mL NSS) was injected through aVeress needle through the incision site for hydrodissection
down to the anterior neck area (Fig. 3A). This hydrodis-
section helps to elevate the subplatysmal plane off the strapmuscles. A medium-sized Kelly clamp was passed through
this incision to the level of the thyroid cartilage and gently
spread to open a working space (Fig. 3B). The hydrodis-section and Kelly clamp dilation helped to approach the
correct plane between the platysma and strap muscles.
Then, a blunt-tip tissue dissector was inserted through theincision and advanced in a fan-shaped manner in the sub-
platysmal plane above the strap muscles to widen the
working space before insertion of a 10 mm trocar(Fig. 3C). CO2 insufflation was then maintained at
Surg Endosc
123
6 mmHg with a flow rate of 15 L/min through the 10 mm
central trocar. Stab incisions were then made with a scalpelfor the lateral ports which were placed lateral to the canine
teeth and on the lower lip to avoid injury to the mental
nerve (Fig. 2B). This is in contrast to the previouslydescribed position (Fig. 2A) [15] which was more medial
and inferior. Two 5 mm trocars were then inserted at the
lateral incisions into the working space. The lateral trocars
were maintained parallel to the 10 mm trocar (Fig. 4).
Initial dissection
After port insertion, an L-hook with monopolar coagulator
and ultrasonic device were used to complete the workingspace (Fig. 5A). The boundaries of the subplatysmal
working space were defined as follows: (1) inferior border
at the sternal notch, (2) lateral borders at the edges of thesternocleidomastoid muscles, and (3) superior border at the
thyroid cartilage. A 30-degree, 10 mm laparoscope was
passed through the central port, with an L-hook cautery,ultrasonic device, and suction–irrigation alternating
between the right and left lateral trocars. The median raphe
of the strap muscles was opened to expose the isthmus,thyroid, and trachea (Fig. 5B). The strap muscles as well as
the sternothyroid muscle were dissected off the thyroid
lobe of interest. A 2/0 silk was passed transcutaneously intothe working space, passed around the strap muscles with
the laparoscopic instruments, and back out through the
skin, where it was used as an external hanging suture to
Table 1 Previous and newindications for TOETVA
Previous indicationa New indication
Inclusion criteria: thyroid diameter\10 cm Inclusion criteria: thyroid diameter\10 cm
Benign tumor Benign tumor
Follicular neoplasm Follicular neoplasm
Papillary microcarcinoma Papillary microcarcinoma
Graves’ disease Graves’ disease
Substernal goiter, grade 1
Exclusion criteria Exclusion criteria
Unfit for surgery Unfit for surgery
Previous neck surgery Unable to tolerate anesthesia
Radiation on the neck
Unable to tolerate anesthesia
Wore dental brace(s)
a Previous indications are from a previous TOETVA report by the authors [15]
Fig. 1 Operative layout
Fig. 2 Three oral vestibularincisions: A previous incision[15]; B new refined incision toprevent mental nerve injury
Surg Endosc
123
assist in elevating the strap muscles laterally (Fig. 5C). At
times, the sternothyroid muscle was divided at the insertion
on the cricoid in order to facilitate the view of the superiorpole.
Thyroid dissection
Dissection of the thyroid lobe began with the pyramidal
lobe and continued inferiorly with the division of theisthmus close to the contralateral thyroid lobe using an
ultrasonic device (Fig. 5D). Subsequently, an avascular
plane between the superior pole and thyroid cartilage,which is called Joll’s space, was opened and elevated to
expose the superior thyroid vessels. Sometimes, the
external branch of the superior thyroid nerve (EBSL) canbe identified in this space, inserting into the cricothyroid
muscle (Fig. 5E). The superior thyroid vessels were then
cut with the ultrasonic device close to the thyroid to pre-serve the EBSL and the upper parathyroid gland (Fig. 5F).
Recurrent laryngeal nerve identification
After superior pole dissection, the thyroid lobe was
retracted to the opposite side using a grasper. This medial-rotation maneuver can help to expose the tracheoe-
sophageal groove. The recurrent laryngeal nerve (RLN) is
identified at the insertion and dissected parallel to the tra-
chea and downwards perpendicular to the inferior thyroid
artery, near the lower parathyroid gland (Fig. 5G). Then,the thyroid gland was cut close to the thyroid capsule in
order to preserve the RLN and lower parathyroid gland.
The remaining ligament of Berry was then divided. Thisprocedure should be performed carefully by keeping the
active blade of the ultrasonic device as far away from the
RLN as possible.
Specimen extraction
After the lobectomy was completed, an endobag with a
purse string suture and long tail was inserted into a 10 mm
trocar with the camera removed. The bag was advancedinto the working space, unrolled, and positioned in such a
way that the free thyroid lobe could be placed into the
endobag and the suture pulled to close the purse-string.Subsequently, the camera and 10 mm trocar were removed
as were the lateral laparoscopic instruments. The bag was
then retracted through the central incision and deliveredinto the vestibule. For a tumor\4 cm, the specimen could
be extracted en bloc through this incision using a ‘‘push
and pull technique’’ (Fig. 5H). The sponge forceps werefirst inserted into the 10 mm-incision, with the thyroid lobe
grasped inside the bag. Subsequently, the thyroid specimen
Fig. 3 Working space creation: A hydrodissection using a Veress needle; B using a Kelly clamp to overpass the chin; C flap creation using arod-shaped dissector
Fig. 4 Three oral vestibuleincisions
Surg Endosc
123
was pulled out with the sponge forceps using the surgeon’s
right hand, while the bottom of the thyroid specimen was
pushed from the outside using the surgeon’s left hand. Withthis maneuver the thyroid lobe could be extracted as a
single intact specimen. For larger tumors, the thyroid
capsule had to be cut 2–3 times using endo-scissors in theendobag under endoscopic view before removing the
smaller specimens, while taking care not to disrupt the
nodule. Cutting and extraction should be performedentirely within the endobag to avoid seeding of the working
space. If total thyroidectomy is necessary, the procedure is
repeated on the contralateral side. For papillary microcar-cinoma patients, central neck lymph node level VI dis-
section was routinely performed in addition to the
previously mentioned steps.Hemostasis was then confirmed. In the case of lobec-
tomy, no surgical drain was needed. In the case of total
thyroidectomy, a surgical drain was placed by making a
separate 5 mm-incision above the clavicle and inserting a
5 mm trocar for a No. 10 Redivac drain. Afterward, the
strap muscles were re-approximated using 3/0 Polyglactinsutures (Fig. 5I). The oral cavity incisions were closed
using 4/0 Polyglactin sutures (Fig. 6).
Postoperative management
A gauze pressure dressing was placed around the chin for24 h. Sipping water was allowed immediately after sur-
gery. Patients received a liquid diet on the day of surgery
(day 0) and a soft diet 1-day postoperatively. Patients wereallowed to rinse their mouths with mouthwash and brush
their teeth at 1 week postoperatively. Intravenous antibi-
otics were given for 48 h and switched to oral antibioticsuntil 7 days postoperatively. If a surgical drain was deemed
necessary, it was removed on day 2 postoperatively.
Average Visual Analog Pain Scale (VAS) were assessed
Fig. 5 Surgical technique: A boundary of the working space;B midline dissection to expose the thyroid and trachea; C externalhanging suture (white arrow); D isthmectomy; E Joll’s space andsuperior poll dissection, external branch of the superior laryngealnerve (black arrow); F upper parathyroid gland; G medial rotation toexpose the RLN (black arrow); H specimen extraction using an
endobag with a ‘‘push and pull technique’’, arrow direction ofspecimen extraction; I strap muscle closure; TI thyroid isthmus, PYpyramidal lobe, TA trachea, LTG left thyroid gland, CC cricoidcartilage, LUP left-upper parathyroid gland, ITA inferior thyroidartery
Surg Endosc
123
daily until day 3 postoperatively. For those patients dis-charged home before 3 days, post-operative VAS scores
were obtained by phone call. Patients were admitted for2–3 days, with follow-up at 1-week, 1-month, 3-month,
6 months and 1 year clinical visits after surgery (Fig. 7).
The patients were assessed for vocal cord function byflexible or rigid laryngoscope at an outpatient clinic.
Hypoparathyroidism was defined with the level of PTH
lower than the lower limit (11 pg/mL).
Results
This series of patients reported herein do not include the
initial series of 60 patients previously published [15]. FromFebruary 2015 to December 2015, 200 patients comprising 8
males (4%) and 192 females (96%) consecutively received
TOETVA. No conversion to conventional open surgery wasnecessary. The mean age of patients was
40.76 ± 12.06 years (16–81 years). From a total of 200
patients, 110 caseswere single thyroid nodule/cyst (55%), 66cases were multinodular goiters (33%), and 13 cases were
Graves’ disease (6.5%), with the remaining 11 cases being
papillary microcarcinoma (5.5%). Hemithyroidectomy wasperformed in 111 cases (55.5%), while total thyroidectomy
or Hartley–Dunhill procedure was performed in 89 cases
(44.5%). The average thyroid nodule size was4.1 ± 1.78 cm (1–10 cm). Median operation time was
97 ± 40.5 min (45–300 min), which was 85 ± 22.42 min
(45–177 min) for hemithyroidectomy and 130 ± 40.38 min(45–300 min) for bilateral thyroidectomy. Median blood
loss was 30 ± 46.25 mL (6–300 mL), which was
20 ± 38.33 min (6–200 min) for hemithyroidectomy and50 ± 52.3 min (7–300 min) for bilateral thyroidectomy.
The average VAS measurements were 2.41 ± 2.04 (0–7),
1.17 ± 1.4 (0–5), and 0.47 ± 0.83 (0–3) on the first, second,
and third post-operative day, respectively. The averagehospital stay was 3.2 ± 0.53 days (2–5 days). The average
length of follow-up is 8.5 months (Table 2).
Temporary hoarseness occurred in 8 patients (2.67%).RLN injury was confirmed by vocal cord motion impair-
ment found on laryngoscopy. Right RLN injury and left
RLN injury occurred in 6 and 2 patients, respectively.Office laryngoscopy was performed at all clinical visits
until 6 months after surgery. Return of normal vocal cordmotion took 2.85 months, on average. No permanent RLN
injury was found.
Temporary hypoparathyroidism was observed in 35patients (17.5%). No permanent hypoparathyroidism
occurred. Lower lip numbness, likely secondary to mental
nerve injury, was found in 3 patients (1.5%) and resolvedin 3 months. Seroma formation was found in 10 patients
(5%) and treated with simple aspiration. Post-operative
hematoma was found in 1 patient and treated with opensurgery. Subcutaneous emphysema was found in 7 patients
(3.5%) and treated by conservative treatment, with reso-
lution within 24 h. No other types of infection or compli-cations were encountered (Table 3).
Discussion
In this study, the largest single-institution case series ofTOETVA to date has been presented, demonstrating the
safety and feasibility of this approach. This technique
evolved out of a mutual desire by patients and surgeonsalike for a scarless, minimally-invasive approach with the
goal of optimizing cosmesis and quality of life after sur-
gery [16–18] while avoiding many of the limitations ofother remote-access approaches to the central neck.
Requisite to adopting any new surgical technique is
scrutiny and analysis to confirm that the procedure is fea-sible and safe with the ultimate comparison to the gold
standard of open transcervical thyroidectomy. To that end,
an international group of surgeons formed the TONS StudyGroup to ensure the responsible adoption and evolution of
this technique while ensuring patient safety. Experienced
surgeons that have experimented with or performed tran-soral thyroidectomy at their respective institutions, whether
endoscopic or robotic, are included in this manuscript
[19–22].Transoral thyroidectomy approaches currently include
both a sublingual [10–12] and an oral vestibular [13–15]
approach. The sublingual approach was first reported in2007 by Witzel et al. [8], who successfully performed
transoral endoscopic thyroidectomy on 10 living pigs using
a single port cervicoscope through the midline of thesublingual area. Benhijeb et al. [9] subsequently reported
Fig. 6 Oral vestibule incisions after suturing
Surg Endosc
123
the performance of this technique on 5 human cadavers in
2009. Later, Karakas et al. [10] reported their experience
on 10 living pigs and 10 human cadavers and performedtransoral endoscopic parathyroidectomy on 2 patients by
placing a 20 mm incision at the lateral floor of the mouth
and using a cervicoscope. However, one patient experi-enced hypoglossal nerve injury. Wilhem et al. [11] also
reported the use of a 1 cm sublingual port combined with5 mm vestibular ports to perform thyroidectomies on 8
patients. Although there remains interest in the sublingual
approach [23], enthusiasm has been dampened by highcomplication rates secondary to violation of the floor of the
mouth, which have made this technique less popular and
widely criticized [24].The oral vestibular approach involves making all inci-
sions anterior to the mandible without violating the floor of
the mouth or ventral tongue. It was first described byRichmon et al. in a cadaveric study exploring a transoral
robotic thyroidectomy approach [19]. In 2013, Nakajo et al.
[13] reported their experience with Transoral Video-As-sisted Neck Surgery (TOVANS) on 8 patients using a
2.5 cm single incision in the oral vestibule with a gasless
technique. One patient developed RLN palsy and all 8
patients developed mental nerve injury. Later, Wang et al.[14] reported a completely oral vestibular approach with 3
ports on 12 patients. Yang et al. [25] also reported the
vestibular procedure on 40 patients with minimal compli-cations. Recently, the first author published a report on his
TOETVA experiences at Police General Hospital inBangkok on the largest series of 60 patients with excellent
results [15]. This report further establishes the transoral
vestibular approach as the preferred transoral technique toaccess the neck. This is due in part to the ease of the
approach, the excellent view of the surgical field afforded
when the camera passes anterior to the mandible, and theavoidance of a sublingual incision with its inherent com-
plications. Moreover, the rapidly accruing world experi-
ence with this technique has demonstrated a very favorablesafety and feasibility profile. The authors’ report bolsters
this experience with the largest case series heretofore
reported and reviewed by the international TONS StudyGroup.
Fig. 7 Postoperative follow-upafter: A 1 week; B 1 month
Surg Endosc
123
Generally, the indications for endoscopic thyroidectomy
include benign disease, papillary microcarcinoma, andthyroid tumor size \6 cm [4–6]. With the TOETVA
technique utilized by the authors, thyroid tumors as large as
10 cm have been removed (personal experience). However,tumors with sizes no larger than 6–8 cm should be con-
sidered as the upper limit, especially for those with limited
experience. In order to remove the thyroid specimenthrough the central vestibular incision, care must be taken
not to rupture the endobag and avoid contamination or
seeding of the tumor to the working space. The centralincision has to be extended to 3 cm and the ‘‘push and pull
technique’’ has been used to extract the specimen in order
to retain an intact capsule and favorable pathological result(Fig. 5H). For benign thyroid disease, such as well-con-
trolled Graves’ disease and goiters\8 cm, the thyroid lobe
must be cut away from the nodule inside the endobag inorder to extract it from the central incision. For thyroid
cancer, the nodule should be limited to \2 cm for
TOETVA. The authors’ nascent experience with this
technique included a small number of patients with papil-lary microcarcinoma who would not require additional
treatment as per the 2015 American Thyroid Association
guidelines [26]. The authors caution against the inclusionof malignant disease at this point, but are very encouraged
by the results of this study. If completion thyroidectomy is
advised in the patients with neoplasm ultimately found tobe thyroid carcinoma, a repeat-TOETVA for the con-
tralateral thyroid gland can be performed within 2 weeks or
after 6 months. On the other hand, transaxillary endoscopicthyroidectomy is another option for completion thy-
roidectomy of the contralateral thyroid lobe. A major
advantage of TOETVA is the midline approach to thecentral neck, which allows access for a total thyroidectomy
and central neck dissection. Such an approach is unparal-
leled compared to other remote-access approaches.Paramount to any thyroid surgery is the identification
and preservation of the RLN. Generally, percentages of
temporary and permanent RLN injury in open thyroidec-tomy procedure range from 2.11 to 11.8% and 0.2 to 5.9%
[27–29], respectively. In this study, temporary and per-manent RLN injury accounted for 2.67 and 0%, respec-
tively, which is a similar rate compared to conventional
open surgery. The TONS Study Group continues to pro-tocolize the meticulous assessment of RLN function, which
will be addressed in future studies.
Identification and preservation of the parathyroid glandsis also critical for any thyroid surgery. TOETVA allows for
easy identification of the glands, which is facilitated by the
magnified, high-definition laparoscopic view. After cutting
Table 2 Demographic data and operative details
Characteristics and details Value
Age (mean, years) 40.76 ± 12.06 (16–81)
Sex (n = 200)
Male 8 (4%)
Female 192 (96%)
Thyroid disease (n = 200)
Single thyroid nodule/cyst 110 (55%)
Multinodular goiter 66 (33%)
Graves’ disease/toxic adenoma 13 (6.5%)
Papillary microcarcinoma 11 (5.5%)
TOETVA procedure (n = 200)
Hemithyroidectomy 111 (55.5%)
Bilateral thyroidectomy 89 (44.5%)
Operative time (median, minutes) 97 ± 40.50 (45–300)
Hemithyroidectomy 85 ± 22.42 (45–177)
Bilateral thyroidectomy 130 ± 40.38 (45–300)
Blood loss (median, mL) 30 ± 46.25 (6–300)
Hemithyroidectomy 20 ± 38.33 (6–200)
Bilateral thyroidectomy 50 ± 52.3 (7–300)
Hospital stay after surgery (mean, days) 3.2 ± 0.53 (2–5)
Tumor size (mean, cm) 4.1 ± 1.78 (1–10)
Conversion to open surgery 1 (0.5%)
Average length of follow-up (months)
VAS pain score (n = 200, mean)
8.5
Day 1 2.41 ± 2.04 (0–7)
Day 2 1.17 ± 1.4 (0–5)
Day 3 0.47 ± 0.83 (0–3)
Table 3 Postoperative complications
Complications Number (n = 200) (rate)
Hypoparathyroidism
Temporary 35 (17.5%)
Permanent 0
Recurrent laryngeal nerve (RLN) injury
Temporary 8 (4%)
Right RLN injury 6
Left RLN injury 2
Permanent 0
Mental nerve injury 3 (1.5%)
Hematoma 1 (0.5%)
Infection 0
Subcutaneous emphysema 7 (3.5%)
Pneumomediastinum 0
Seroma 10 (5%)
Tracheal injury 0
Esophageal injury 0
Surg Endosc
123
the super thyroid vessels and elevating the superior thyroid
lobe to the opposite side, the superior parathyroid glandwas often visualized (Fig. 4F). This, in combination with
the RLN, was helpful in identifying the inferior parathyroid
gland. The transient and permanent hypoparathyroidismrates were 17.5 and 0%, respectively, comparable to those
of standard open thyroidectomy (0–11% and 0–5.7%,
respectively [27, 28, 30, 31]).The transoral approach to the neck must be considered
clean-contaminated surgery and carries an inherentlygreater risk of infection than clean transcervical thy-
roidectomy [32]. Nonetheless, the authors did not observe
any post-operative infections in this large case series,which is likely due to the meticulous oral preparation and
peri-operative administration of antibiotics.
Seroma formation is a minor complication of endo-scopic thyroidectomy [33]. Patients may be at greater risk
of seroma formation given the larger flap elevation nec-
essary to create a working space. Ten patients (5%)experienced seromas, all of which were treated with simple
aspiration without further sequela.
The mental nerves exit from the mental foramenbetween the first and second premolars. The nerves provide
sensory innervation to the chin and lower lip. Previous
reports of the transoral approach document a high com-plication rate for mental nerve injury [11, 13, 14]. In
contrast to previous studies, the authors documented a very
low rate (1.5%) of transient nerve injury, which completelyrecovered within 2–4 months. However, the 5 mm inci-
sions in the first 100 cases were close to the center inci-
sions, as described in a previous study [15]. Mental nerveinjury was found in 3 patients. Therefore, the authors
refined both 5 mm incisions to make them as lateral as
possible, lateral to the canine teeth, and very close to thelower lip (Fig. 2B). With these new incisions, there was no
mental nerve injury in the cases that followed. This was
likely due to modification of the location for the lateral portincisions closer to the free lip edge, which allowed for
greater mobility of the lip during the procedure while
imparting less tension on the mental nerve where it exitsthe foramen.
We understand that the average length of stay in this
study is longer than that typically experienced in the West,especially the United States. There are many factors
involved in LOS beyond that of just the medical condition
of the patient, including reimbursement models and socialand cultural expectations. In Asian countries, it is com-
mon for patients to remain in the hospital for the duration
of recuperation from surgery rather than transition post-operative care to home. We did not experience any dif-
ference in LOS between those patients receiving
TOETVA versus conventional open thyroidectomy in ourhospital. Furthermore, there has been experience with safe
overnight hospitalization after TOETVA by other authors
in this manuscript and in the literature [34]. While theindications for thyroid surgery continue to evolve and the
authors acknowledge that there are patients in this series
who would be candidates for observation under newguidelines [26], the purpose of this report was to further
characterize the transoral thyroidectomy approach. There
has been a great deal of enthusiasm for the TONSapproach, with many surgeons around the world poised to
introduce this technique at their hospitals. The TONStechnique is challenging, even for the most experienced
surgeon, with a steep learning curve. This procedure
should not be undertaken by an inexperienced thyroidsurgeon. Furthermore, this approach involves several skills
in which most thyroid surgeons may not be adept,
including advanced laparoscopy skills and working withina narrow working space in the neck. Both transoral robotic
and endoscopic thyroidectomy approaches are currently
being utilized by members of the TONS Study Group. Itcannot be over-emphasized that appropriate preparation is
necessary to perform this surgery successfully. This goes
beyond just the surgeon and requires that all operatingroom staffs are familiar with the procedure. The authors
submit that this requires case observations, cadaveric
dissections, and mentored initiation of one’s first cases toensure the requisite skills and familiarity with this novel
procedure.
Conclusion
The authors report the largest single-institution case series
of TOETVA to date with an excellent safety and feasi-
bility profile. The advantages of this technique over otherremote access approaches include its ability to afford
equal access to both sides of the neck, the decreased
tissue dissection required, and the excellent view of theanatomy provided, similar to an open approach. Further, it
is the only approach that avoids any cutaneous scarring.
The TONS Study Group will continue to evaluate thistechnique using both robotic and endoscopic instrumen-
tation while measuring functional, cosmetic, and quality-
of-life outcomes.
Funding No grant support was received for this study.
Compliance with ethical standards
Disclosures Dr. Angkoon Anuwong, Dr. Thanyawat Sasanakietkul,Dr. Pornpeera Jitpratoom, Dr. Khwannara Kantha, Dr. Hoon YubKim, Dr. Gianlorenzo Dionigi and Dr. Jeremy Richmon have noconflicts of interest or financial ties to disclose related to the workherein.
Surg Endosc
123
References
1. Ferzli GS, Sayad P, Abdo Z, Cacchione RN (2001) Minimally-invasive, non-endoscopic thyroid surgery. J Am Coll Surg192:665–668
2. Rafferty M, Miller I, Timon C (2006) Minimal incision for openthyroidectomy. Otolaryngol Head Neck Surg 135:295–298
3. Miccoli P, Berti P, Conte M, Bendinelli C, Marcocci C (1999)Minimally invasive surgery for thyroid small nodules: prelimi-nary report. J Endocrinol Invest 22:849–851
4. Ikeda Y, Takami H, Niimi M, Kan S, Sasaki Y, Takayama J(2001) Endoscopic thyroidectomy by the axillary approach. SurgEndosc 15:1362–1364
5. Choe J (2007) Endoscopic thyroidectomy using a new bilateralaxillo-breast approach. World J Surg 31:601–606
6. Wang C, Feng Z, Li J, Yang W, Zhai H, Choi N, Yang J, Hu Y,Pan Y, Cao G (2015) Endoscopic thyroidectomy via areolaapproach: summary of 1,250 cases in a single institution. SurgEndosc 29:192–201
7. Park JO, Kim SY, Chun BJ, Joo YH, Cho KJ, Park YH, Kim MS,Sun DI (2015) Endoscope-assisted facelift thyroid surgery: aninitial experience using a new endoscopic technique. Surg Endosc29:1469–1475
8. Witzel K, von Rahden BH, Kaminski C, Stein HJ (2008) Tran-soral access for endoscopic thyroid resection. Surg Endosc22:1871–1875
9. Benhidjeb T, Wilhelm T, Harlaar J, Kleinrensink GJ, SchneiderTA, Stark M (2009) Natural orifice surgery on thyroid gland:totally transoral video-assisted thyroidectomy (TOVAT): reportof first experimental results of a new surgical method. SurgEndosc 23:1119–1120
10. Karakas E, Steinfeldt T, Gockel A, Westermann R, Kiefer A,Bartsch DK (2010) Transoral thyroid and parathyroid surgery.Surg Endosc 24:1261–1267
11. Wilhelm T, Metzig A (2011) Endoscopic minimally invasivethyroidectomy (eMIT): a prospective proof-of-concept study inhumans. World J Surg 35:543–551
12. Woo SH (2014) Endoscope-assisted transoral thyroidectomyusing a frenotomy incision. J Laparoendosc Adv Surg Tech A24:345–349
13. Nakajo A, Arima H, Hirata M, Mizoguchi T, Kijima Y, Mori S,Ishigami S, Ueno S, Yoshinaka H, Natsugoe S (2013) Trans-OralVideo-Assisted Neck Surgery (TOVANS). A new transoraltechnique of endoscopic thyroidectomy with gasless premandibleapproach. Surg Endosc 27:1105–1110
14. Wang C, Zhai H, Liu W, Li J, Yang J, Hu Y, Huang J, Yang W,Pan Y, Ding H (2014) Thyroidectomy: a novel endoscopic oralvestibular approach. Surgery 155:33–38
15. Anuwong A (2016) Transoral endoscopic thyroidectomyvestibular approach: a series of the first 60 human cases. World JSurg 40:491–497
16. Koo DH, Kim DM, Choi JY, Lee KE, Cho SH, Youn YK (2015)In-depth survey of scarring and distress in patients undergoingbilateral axillo-breast approach robotic thyroidectomy or con-ventional open thyroidectomy. Surg Laparosc Endosc PercutanTech 25:436–439
17. Arora A, Swords C, Garas G, Chaidas K, Prichard A, Budge J,Davies DC, Tolley N (2016) The perception of scar cosmesisfollowing thyroid and parathyroid surgery: a prospective cohortstudy. Int J Surg 25:38–43
18. Lee MC, Park H, Lee BC, Lee GH, Choi IJ (2016) Comparison ofquality of life between open and endoscopic thyroidectomy forpapillary thyroid cancer. Head Neck 38(Suppl 1):E827–E831
19. Richmon JD, Holsinger FC, Kandil E, Moore MW, Garcia JA,Tufano RP (2011) Transoral robotic-assisted thyroidectomy with
central neck dissection: preclinical cadaver feasibility study andproposed surgical technique. J Robot Surg 5:279–282
20. Lee HY, Richmon JD, Walvekar RR, Holsinger C, Kim HY(2015) Robotic transoral periosteal thyroidectomy (TOPOT):experience in two cadavers. J Laparoendosc Adv Surg Tech A25:139–142
21. Lee HY, You JY, Woo SU, Son GS, Lee JB, Bae JW, Kim HY(2015) Transoral periosteal thyroidectomy: cadaver to human.Surg Endosc 29:898–904
22. Clark JH, Kim HY, Richmon JD (2015) Transoral robotic thyroidsurgery. Gland Surg 4:429–434
23. Cai C, Huang Y, Zhang T, Chai L, Wang G, Shi L, Wiegand S,Guldner C, Gunzel T, Wilhelm T (2015) Anatomical study ofsurgical approaches for minimally invasive transoral thyroidec-tomy: eMIT and TOPP. Minim Invasive Ther Allied Technol24:340–344
24. McHenry CR (2011) Endoscopic minimally invasive thyroidec-tomy: a prospective proof-of-concept study in humans. World JSurg 35:552
25. Yang J, Wang C, Li J, Yang W, Cao G, Wong HM, Zhai H, LiuW (2015) Complete endoscopic thyroidectomy via oral vestibularapproach versus areola approach for treatment of thyroid dis-eases. J Laparoendosc Adv Surg Tech A 25:470–476
26. Haugen BR, Alexander EK, Bible KC, Doherty GM, Mandel SJ,Nikiforov YE, Pacini F, Randolph GW, Sawka AM, Schlum-berger M, Schuff KG, Sherman SI, Sosa JA, Steward DL, TuttleRM, Wartofsky L (2016) 2015 American Thyroid Associationmanagement guidelines for adult patients with thyroid nodulesand differentiated thyroid cancer: the American Thyroid Asso-ciation guidelines task force on thyroid nodules and differentiatedthyroid cancer. Thyroid 26:1–133
27. Song CM, Jung JH, Ji YB, Min HJ, Ahn YH, Tae K (2014)Relationship between hypoparathyroidism and the number ofparathyroid glands preserved during thyroidectomy. World J SurgOncol 12:200. doi:10.1186/1477-7819-12-200
28. Ywata de Carvalho A, Chulam TC, Kowalski LP (2015) Long-term results of observation vs prophylactic selective level vi neckdissection for papillary thyroid carcinoma at a cancer center.JAMA Otolaryngol Head Neck Surg 141:599–606
29. Calo PG, Pisano G, Medas F, Pittau MR, Gordini L, Demontis R,Nicolosi A (2014) Identification alone versus intraoperativeneuromonitoring of the recurrent laryngeal nerve during thyroidsurgery: experience of 2034 consecutive patients. J OtolaryngolHead Neck Surg 43:16. doi:10.1186/1916-0216-43-16
30. Selberherr A, Scheuba C, Riss P, Niederle B (2015) Postoperativehypoparathyroidism after thyroidectomy: efficient and cost-ef-fective diagnosis and treatment. Surgery 157:349–353
31. Seo GH, Chai YJ, Choi HJ, Lee KE (2016) Incidence of per-manent hypocalcaemia after total thyroidectomy with or withoutcentral neck dissection for thyroid carcinoma: a nationwide claimstudy. Clin Endocrinol 85:483–487
32. Yang CH, Chew KY, Solomkin JS, Lin PY, Chiang YC, Kuo YR(2013) Surgical site infections among high-risk patients in clean-contaminated head and neck reconstructive surgery: concordancewith preoperative oral flora. Ann Plast Surg 71(Suppl 1):S55–S60
33. Shan CX, Zhang W, Jiang DZ, Zheng XM, Liu S, Qiu M (2010)Prevalence, risk factors, and management of seroma formationafter breast approach endoscopic thyroidectomy. World J Surg34:1817–1822
34. Udelsman R, Anuwong A, Oprea AD, Rhodes A, Prasad M,Sansone M, Brooks C, Donovan PI, Jannitto C, Carling T (2016)Trans-oral vestibular endocrine surgery: a new technique in theUnited States. Ann Surg 264:e13–e16
Surg Endosc
123